Strata mining-adjacent seam hardness indicator



March 17, 1959 G. T. FELBECK STRATA MINING-ADJACENT SEAM HARDNESSINDICATOR Filed Nov. 18, 1954 2 Sheets-Sheet 1 March 17, 1959 G. T.FELBECK .2878000 STRATA MINING-ADJACENT SEAM HARDNESS INDTCATOR` I,Filed Nov. 18. 1954 2 Sheets-Sheet 2 i' 25 25d l 34 25 25d l I l I, "1 lVINVENTOR ATTORN y ciones I. FELBEcK g5.

United States Patent() STRATA MINING-ADJACENT SEAM HARDNESS INDICATORGeorge T. Felbeck, Wernersville, Pa., assignor to Union CarbideCorporation, a corporation of New York Application November 18, 1954,Serial No. 469,586

1 Claim. (Cl. 262-7) This invention relates to selected earth stratamining by remote control, and more particularly to improved means 'forindicating at a remote control station the relative hardness-of aseamabove or below the selected strata being mined before the mining machinecutters are damaged in case the machine approaches a seam that is hardenough to damage such cutters.

The invention is very useful in providing information for controllingthe course of a mining machine of the type disclosed in the patentapplication of Alspaugh et al., Serial No. 353,932, filed May 11, 1953,now Patent No. 2,826,402, for a Remotely Controlled Mining System.

l In a continuous mining process using a machine controlled at a pointremote from the actual mining operation, it is desirable to know at thecontrol station if and when the machine approaches or crosses an upperor lower boundary of the strata or seam being mined.

An object of this invention is to provide information as soon aspossible at the remote control station by a meter change if the machineleaves, or is likely to leave a selected seam, and approaches or entersa seam of different character, either above or below it, before the mainhead cutters are damaged.

For example, in mining coal the machine should operate only in theselected coal seam or strata, and if it can be avoided, not engage arock strata immediately above or below such coal seam, else the cutterswill be damaged, resulting in costly loss of operating time while Qthedamage is being repaired.

This invention involves the use of a drum type cutter mounted on abore-mining machine and so arranged as to cut selected strata in adirection normal to the forward motion of the machine, a motor to drivesuch drum cutter, and a suitable meter located at the remote controlpoint of the mining machine connected to indicate the power supplied tosuch drum cutter drive motor. Changes in the meter reading indicatechanges in the power requirements of the motor, and hence changes in theforce required by the drum cutter to cut earth strata material adjacentto the bore made by the mining machine. As the machine bores forwardinto coal, for example, such a drum cutter transversely mounted on topof the machine removes cusps of coal from the roof. The meter indicatesthe measure of force required for cutting such coal. As the machineapproaches a layer of different hardness, such as rock in the top, forexample, before the main cutter head teeth hit a relatively hard layerthe drum cutter engages such harder layer. The resulting change in meterreading immediately indicates to the operator that the machine is movingup` wardly toward such layer of diierent hardness. He immediatelychanges the vertical course of the machine so as to avoid such harderlayer and remain in the selected coal strata.

A similar situation exists with respect to the bottom drum cutter. Ifthe machine proceeds on a downward course, the bottom drum cuttereventually breaks through ICC the boundary of the coal into the bottom.The resulting change in the lower drum cutter power requirementindicates to the operator that such cutter has broken through the bottomofthe coal seam, and he thereupon changes the vertical course of themachine so that the machine will avoid such bottom progress and progressonly in the desired coal seam.

Wear on the drum cutter teeth is reduced by having a few of the teeththereof longer than theothers and thus concentrating wear in such longerteeth.

In the drawing:

Fig. v1 is a view partly in section and partly in side elevation of amining system embodying the invention 1n use;

Fig. 2 is a fragmentary top plan view of the machine in the bore-hole;

Fig. 3 is an enlarged cross sectional view of the borehole between thefront cutters and the upperv and lower drum cutters; and

Figs. 4 and 5 are enlarged fragmentary top plan views of the machineshowing the upper and lower drum cutters, respectively.

The mining machine 10 comprising a self-powered tractor-type body 11 isdesigned to bore a hole 12 in selected earth strata, such as a coal seam14, under the supervision of an operator in a control house 16 locatedoutside of such borehole, as disclosed in said application Serial No.353,932, continuously mining the material of such strata as the machineadvances a distance, for example, of 1000 feet-more or less-without theneed for a man to enter the hole.

The rotary front cutters 18 being laterally spaced leave cusps 20 ofselected strata material in the oor and roof of the bore-hole, which areremoved and such material recovered by the transversely disposedelongated upper and lower rotary drum cutters 22 and 24. The drumcutters are provided with radial teeth 25 some of which 25a are longerthan the others for the purpose of concentrating wear therein, andminimizing wear or darnage to the other teeth.

The upper cutter 22 is mounted on arms 26 pivoted to a main (front) gearbox 28 by means of a transverse torsion shaft 30 that biases the upperdrum cutter 22 upwardly toward the roof of the bore-hole. Such frontgear box 28 is mounted on the body 11 for adjustment about a transversehorizontal axis to control the vertical course of the machine. The upperdrum cutter 22 is driven by an electric motor 32 through suitablereducing gear means 34 carried by the left one of arms 26.

The lower drum cutter 24 is driven by a motor 36 through suitable meanscomprising a drive shaft 38 containing universal joints 40 and 42, adifferential gear 44, transverse drive shafts 46, and reduction gearmeans 48 disposed on each side of the machine. The ends of the lowerdrum cutter 24 are carried by gear boxes 50 that are mounted on the siderails 52 of therconveyors 54 which are disposed on either side of thelongitudinal center of the machine, and pivoted at 56 forself-adjustment as the contour of the iloor varies. Thus, as the lowerdrum cutter 24 approaches a seam of hard stratum such as sandstone, forexample, below the selected strata being mined by the system, the torqueof the motor 36 increases, which fact is indicated by a meter 58 locatedin the control house 16.

Similarly, a meter 60 that is electrically connected to the motor 32which drives the upper drum cutter 22 indicates when the latterapproaches a seam of relatively hard earth material above the roof ofthe hole 12. With such information, the operator can control thevertical course of the machine at the panel 62 to keep the progress ofthe mining operation within the selected strata and avoid any damage tothe front cutters as well as to the drum cutters of the machine.Suitable vertical controls are ydisclosed in said application Serial No.353,932, and in the application of Heimaster et al., Serial No. 307,246,tiled August 30, 1952, now Patent No. 2,761,666, for Remotely ControlledBore-Mining Machine-Automatic Course Controller.

In this invention the drum cutters serve not only vto cut (mine) asubstantial amount of the selected strata material, such as coal, butthey also'serve at the same time to supply information as to therelative hardness of the material being cut 'much more quickly `and withless chance of damage to the cutters than has beenpossible in the past,because the load on a drum cutter (about 7 feet long) increases lrather.rapidly as it 'appreaches a harder stratum than coal, for example, Aandthus indicates possible damage to the lcutters to the operator at thecontrol 'station before any actual :damage occurs to the cutter teetheven in the front cutters.

Applications ySerial No. 307,246 and lSerial No. 353,932 have beenassigned to Union Carbide and Carbon Corporation, assignee of thepresent application.

`I claim:

In a bore mining machine the combination'comprising a self-poweredtractor-type body, a frontgear box mounted on said body for adjustmentabout a transversehorizontal axis, front rotary cutters mounted 4on saidgear box for rotation about transversely `spaced longitudinal-horizontalaxes, means for driving said front cutters in unison through said frontgearbox, longitudinal continuous conveyors mounted within said body koneither side of the longitudinal center thereof and hardness, and meansfor controlling the vertical course of the machine vto keep it withinselected earth `strata as revealed by said instruments, said drumcutters cornprising radial teeth some of which are longer than othersfor the purpose of concentrating wear thereon due to engagement withharder layers of earth strata in the oor `and 'roof of the .bore-hole,Vsaving the other teeth from damage thereby.

References Cited in the tile ofthis patent UNITED STATES PATENTS1,645,007 Johansen Oct. 11, 1927 2,694,562 Snyder et al. Nov. 16, 19542,699,328 Alspaugh et al. Ian. 11, 1955 2,734,731 Cartlidge et al. Feb.14, 1956

